Tidy up trimdomain() and document it.

Don't truncate one byte short of the passed length.

3 files changed, 76 insertions, 12 deletions

diff --git a/lib/libutil/Makefile b/lib/libutil/Makefile
index 9e9d04b..dddf945 100644
--- a/lib/libutil/Makefile
+++ b/lib/libutil/Makefile
@@ -10,7 +10,8 @@ SRCS=	login.c login_tty.c logout.c logwtmp.c pty.c setproctitle.c \
 	_secure_path.c uucplock.c property.c auth.c realhostname.c
 MAN3+=	login.3 login_auth.3 login_tty.3 logout.3 logwtmp.3 pty.3 \
 	setproctitle.3 login_cap.3 login_class.3 login_times.3 login_ok.3 \
-	_secure_path.3 uucplock.3 property.3 auth.3 realhostname.3
+	_secure_path.3 uucplock.3 property.3 auth.3 realhostname.3 \
+	trimdomain.3
 MAN5+=	login.conf.5 auth.conf.5
 MLINKS+= property.3 properties_read.3  property.3 properties_free.3
 MLINKS+= property.3 property_find.3
diff --git a/lib/libutil/logwtmp.c b/lib/libutil/logwtmp.c
index 9759578..acbb4c9 100644
--- a/lib/libutil/logwtmp.c
+++ b/lib/libutil/logwtmp.c
@@ -36,7 +36,7 @@
 static char sccsid[] = "@(#)logwtmp.c	8.1 (Berkeley) 6/4/93";
 #else
 static const char rcsid[] =
-	"$Id: logwtmp.c,v 1.8 1998/10/09 11:24:19 jkh Exp $";
+	"$Id: logwtmp.c,v 1.9 1999/04/07 08:27:04 brian Exp $";
 #endif
 #endif /* LIBC_SCCS and not lint */
 
@@ -55,7 +55,7 @@ static const char rcsid[] =
 #include <utmp.h>
 
 void
-trimdomain( char * fullhost, int hostsize )
+trimdomain(char *fullhost, int hostsize)
 {
     static char domain[MAXHOSTNAMELEN];
     static int first = 1;
@@ -67,21 +67,18 @@ trimdomain( char * fullhost, int hostsize )
             (s = strchr(domain, '.')))
             bcopy(s + 1, domain, strlen(s + 1) + 1);
         else
-            domain[0] = 0;
+            domain[0] = '\0';
     }
 
-    if (domain[0]) {
-		s = fullhost;
-        while ((fullhost = strchr(fullhost, '.'))) {
+    if (domain[0] != '\0') {
+	s = fullhost;
+        while ((fullhost = strchr(fullhost, '.')) != NULL)
             if (!strcasecmp(fullhost + 1, domain)) {
-		if ( fullhost - s  < hostsize ) {
+		if (fullhost - s  <= hostsize)
                		*fullhost = '\0';    /* hit it and acceptable size*/
-		}
                 break;
-            } else {
+            } else
                 fullhost++;
-            }
-        }
     }
 }
 
diff --git a/lib/libutil/trimdomain.3 b/lib/libutil/trimdomain.3
new file mode 100644
index 0000000..57e476f
--- /dev/null
+++ b/lib/libutil/trimdomain.3
@@ -0,0 +1,66 @@
+.\" Copyright (c) 1999 Brian Somers <brian@Awfulhak.org>
+.\" All rights reserved.
+.\"
+.\" Redistribution and use in source and binary forms, with or without
+.\" modification, are permitted provided that the following conditions
+.\" are met:
+.\" 1. Redistributions of source code must retain the above copyright
+.\"    notice, this list of conditions and the following disclaimer.
+.\" 2. Redistributions in binary form must reproduce the above copyright
+.\"    notice, this list of conditions and the following disclaimer in the
+.\"    documentation and/or other materials provided with the distribution.
+.\"
+.\" THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
+.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+.\" ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
+.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+.\" SUCH DAMAGE.
+.\"
+.\"	$Id: realhostname.3,v 1.1 1999/04/06 23:02:35 brian Exp $
+.\"
+.Dd April 7, 1999
+.Os
+.Dt TRIMDOMAIN 3
+.Sh NAME
+.Nm trimdomain
+.Nd "trim the current domain name from a host name"
+.Sh SYNOPSIS
+.Fd #include <libutil.h>
+.Ft void
+.Fn trimdomain "char *fullhost" "int hostsize"
+.Pp
+Link with
+.Va -lutil
+on the
+.Xr cc 1
+command line.
+.Sh DESCRIPTION
+The function
+.Fn trimdomain
+removes the current domain name from the passed
+.Ar fullhost
+name by writing a
+.Dv NUL
+character over the first period of the passed name.  The current domain
+name is determined by calling
+.Xr gethostname 3
+and removing everything up to the first period.  The name is determined
+the first time this function is called and is cached for future use.
+.Pp
+.Fn trimdomain
+will only trim the domain name if the passed
+.Ar fullname
+ends with the current domain name and if the length of the resulting host
+name does not exceed
+.Ar hostsize .
+.Sh RETURN VALUES
+.Fn trimdomain
+does not return a value.
+.Sh SEE ALSO
+.Xr gethostname 3